# DC_StoreRange

## C Specification

      #include <nitro/os.h>

      void DC_StoreRange( void* startAddr, u32 nBytes );

      void DC_CleanRange( void* startAddr, u32 nBytes );

## Description

This function stores in the specified region of data cache to memory. Specifically, it performs a cache writeback in a dirty state (state when a write to data cache corresponding to a specified memory region is not reflected in main memory), discards all data in cache, and places it in an clean state (state where all stored values in cache match memory contents).

Use when completing data transmission data blocks that use the main memory of other devices, such as when performing DMA transfers or creating graphics commands.

`DC_CleanRange()` is another name for `DC_StoreRange()` and operates exactly the same.
`startAddr` is rounded down to the closest 32-byte boundary. `startAddr` + `nBytes` is rounded up to the closest 32-byte boundary.

`DC_Clean*/DC_CleanAndInvalidate*` were prepared for porting from the prototype SDK version. Normally, `DC_Store*/DC_Flush*` should be used.

The official documentation for the ARM processor sometimes describes Flush as the operation that invalidates the data cache, Clean as the operation that writes back the data cache and puts it into a clean state, and Clean and Flush as the operation that writes back and then invalidates. However, this SDK follows the conventions of the Nintendo GameCube and Nintendo64 by using Invalidate for invalidation, Store for writeback, and Flush for writeback and invalidate operations.

## Internal Operation

Operates register 7 of the system control coprocessor.

## Arguments

`startAddr` | Lowest address in the region to be cleaned
`nBytes` | Number of bytes of the region to be cleaned

## Return Values

None.

## See Also

`IC_InvalidateAll, IC_InvalidateRange, DC_InvalidateAll, DC_InvalidateRange, DC_StoreRange, DC_FlushAll, DC_FlushRange`

## Revision History

12/22/2003 Initial Version